In recent years, electrical storage devices such as non-aqueous electrolyte solution secondary cells and electric double layer capacitors have been widely studied with the increase in demand for solving environmental problems or establishing a sustainable recycling-based society. For example, lithium-ion batteries have high working voltage and energy density, and are therefore used as power sources of laptops, mobile phones, and the like. Such lithium-ion batteries are promising because they have higher energy density than lead batteries and nickel-cadmium batteries to achieve higher capacity.
However, lithium-ion batteries have a problem in that the battery capacity is reduced after repeating a charge/discharge cycle. This is because repeating a charge/discharge cycle over a long period of time causes, for example, decomposition of an electrolyte solution due to electrode reaction, reduction of impregnation of an electrolyte into an electrode active material layer, or reduction of intercalation efficiency of lithium ions.
In order to suppress reduction of a battery capacity due to repeating a charge/discharge cycle, addition of a variety of additives to an electrolyte solution is considered. An additive decomposes during an initial charge/discharge cycle and forms a solid electrolyte interface (SEI) as a film on the surface of an electrode.
Since an SEI is formed during an initial charge/discharge cycle, electricity is not consumed for decomposition of a solvent of an electrolyte solution, and lithium ions can transfer between electrodes through the SEI. That is, formation of an SEI prevents degradation of electrical storage devices such as non-aqueous electrolyte solution secondary cells after repeating a charge/discharge cycle, and contributes to an improvement of cell performance, storage characteristics, load characteristics, and the like.
Patent Literatures 1 to 3 disclose, for example, a cyclic mono-sulfonic acid ester as an additive for an electrolyte solution capable of forming an SEI. Patent Literature 4 discloses a sulfur-containing aromatic compound. Patent Literature 5 discloses a disulfide compound. Further, Patent Literatures 6 to 9 disclose disulfonic acid esters.
Patent Literatures 10 to 13 disclose an electrolyte solution containing vinylene carbonate and vinyl ethylene carbonate. Patent Literatures 14 and 15 disclose an electrolyte solution containing 1,3-propane sultone and butane sultone.